Light emitting diodes (LEDs) may produce a large amount of heat in some applications. One such application may be an array of high power LEDs used to form a light source for luminaires. The heat generated must be removed.
To accomplish this, the LEDs are typically mounted on a metal core printed circuit board (MCPCB) rather than using a conventional printed circuit board composed of a dielectric substrate, such as glass-reinforced epoxy laminate PCBs.
A MCPCB may include a metal substrate, such as aluminum, a dielectric layer over the metal substrate and a patterned metal layer over the dielectric layer. The patterned metal layer may be composed of copper. The patterned metal layer may connect the LEDs to a source of power. The metal substrate may then be thermally and/or electrically coupled to a grounded metal heat sink or it may be floating.
The MCPCB may have better thermal performance than other PCBs due to the relative thickness of the metal substrate which may improve lateral heat spreading and heat dissipation to a heat sink.